Machine for bending tubes and the like



Dec. 29, 1925. i 1,567,107

C. R. H. BONN MACHINE FOR BENDING TUBES AND THE LIKE wwwffww Dec.- 2K9, 1925;'

C. R. H. BONN MACHI/NE FOR BENDING TUBES AND THE LIKE vFiled August 4. 1922 4 Sheets-Sheet 2 Dec.' 29- 1925 A '1,567,1o7m

C. R. H. BONN MACHINE FOR BENDING TUBES AND THE LIKE Filed August 4, 41922 4 sheets-sheet s 13:11@ lib- #6 56.20.

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Dem 29,1925z L56Z1G7 C.R.H.BONN

MACHINE Foa EENDING TUBES AND THE LIKE Filed August 4, 1922' 4 sheets-sheet 4 To all whom it may opneem:

Patented Dec. 29, 1925.

UNITED' STATES CARL ROBERT HUGO BONN, OF HIILHEAD, GLASGOW, SCOTLAND.

MACHINE ron BENDLNG Turns AND THE LIKE.

Animation mea August 4, 1922. semi No. 579,673.

Be it known that I, CARL ROBERT Hueo BONN, a sub'ect of the King of Great Britain and reland and the Isle of Man, and a resident of 56 Gibson Street, Hillhead, Glasgow, Scotland, have invented new and useful Improvements in Machines for Bending Tubes and the like, of which the following is a specication.

This invention has reference to improvements in machines for bending 'tubes and the like and comprises the method of and means Jfor bending tubes and the like such .as rods which consists in gripping the tube adjacent tothe part which `-is to be bent in a clamp constrained to move in the path of the bend` and in moving and guidin the tube endways so that it is fed roun the bend as it is formed; the movement of the clamp being accomplished preferably by the moving tube or by gearing synchronizing with the mechanism for moving the tube or by both nieansf The tube inmoving endways does not begin to bend tillit has passed a guide rollercand when the tube is to be bent into a segment of a circle the axis of this roller is on or near a center line passing through the'center of rotation ofthe clamp and at V right angles to the endways moving tube.

To prevent the tube from being distorted a mandrel may be arranged within the tube and located at or alittle beyond the guide roller. The distance of the .clam from its center of rotation would be varied as the radius of the bend desired varies and'in order that bends of dierent radii may be bent as desired the tube would be adjustable towards or from thecenter of rotation of 'the clamp either by its carrier being pivoted or mounted upon suitable/slides, or by mounting the axis about which the clamp swings in adjustable bearings. be used to bend rods by dispensing with the mandrel while the tube may be coiled into a spiral or volute by suitable attachments hereinafter described.

In order that others skilled in the art to which this invention relates may properly understand the same 1 have hereunto appended four sheets of explanatory drawings in which Figures 1 and 2 are respectively an elevation and a plan view of a machine cona slightly modified form of The machiney may struct'ed` according to this invention for bending tubes. 1

Figs. 3, 4, 5, and 6 are taken on the hnes A. B. res ectively.

1g. 7 is an elevation showing the tube, being bent, in section.

Figs. 8, 9, 10,11, and 12 are views similar to Fig. 7 but illustrate modified forms of mandrels to which reference will be made hereinafter more particularly.

Figs. 13, '14, 15, and 16 illustrate various forms of clamps for the tube.

Each figure comprises a longitudinal sectional elevation and sections taken on the lines E. and F. respectively.

Figs. 17 and 18 each com rise a longitudinal sectional elevation an tional elevations on the lines E. and F. of

transverse sections C. and D. of Fig. 2,

transverse secl a clamp for the tubes in which a `mandrel is angles to each other and Fig. 21 is a sectional view of a clamp for the tube for use lwhen it is desired to bend a tube already ent.

Figs. 22, 23 and 24 are similar views of clamp for the same purpose.

Figs. 25, 26 and 27 are diagrammatic views illustrating the operations of the machine: Figs. 25 and' 26 being elevations at ri ht .angles to each otherand Fig. 27 being a p an 'oted at its one end 2, and provided with a ram 3 arranged within a cylinder 4 which is provided with the usual connections for hydraulic or other pressure fluid.

The Tam 3 S, Stationary .and the cylinder ioo 4 isiadapted to slide thereon onsuitable guides provided on the sole plate 1. The one side of the cylinder 4 is formed with a flat surface or face 5 a ainst which the tube 14 to be bent rests en is clamped by means of a clamp 6. If desired this flat surface 5 may be provided with a V or other suitably shaped roove into which the tube 14 may be clamped? of 'blocks 7 which may engage each other by means of shoulders or steps 8 and which are formed with V shaped or as shown curved faces adapted to contain the tube' 14. A binding strap 9 provided with iianged ends adapted to engage the interrupted projecting flanges 10 of the side 5of the cylinder 4 embraces these bl'ocks 7 which are .secured together by means of a wedge or the like 11. The position of this clamp. 6 may be adjusted along the cylinder as desired to suit the tube which is to be bent.

At a suitable position adjacent to the sole plate'l a vertical spindle or axis 12is mounted in suitable bearings 13. The distance between this spindle 12 and the center of the tube would equal the radius of the bend which is to be given to the tube 14. This vdistance may be regulated by moving the sole platel on its pivot 2 or by moving the sole plate (and therefore the cylinder 4 and the tube 14) in a parallel direction away from or towards the spindle 12 or if desired the sole plate 1 and lts fittings-may be stationary and the bearings of the spindle 12 maybe adjustable to and from the sole plate 1.

When the sole late 1 is pivoted, as illustrated, a slidingb eck-15 (Figs. 2 and 4) may be provided to -hold same rigid after its position has been adjusted. This block 15 may be operated by a screwed rod 16. To slacken back the face 5 from the tube 14 after the operation of bending an eccentric 17 and sliding block. 71 operated by a handle 18A ed. A guide roller 19 ada ted may be arrang to bear'against the tube 14 is varrange in lsuch a position that the tube cannot bend till Iit has passed same. When the bend desired forms a segment. of a circle this roller 19 would be arranged von a line (or approximately on a line) passing through the axis 12 and at ,right angles to the tube 14. Preferably and as illustrated by Figs. 1, 2 andv 5 the roller 19 is carried by an arm or rod 20 mounted in a bracket 21 formed or provided on the sole plate 1. The distance of this roller 19 from the tube may be adjusted by a screw 22 so that the roller presses against the tu e 1.

When tubes ofa di'erent size have to be or smaller one as esired.

The vertical spindle or axis 12 is provided at its upper end with a radial arm 23 having Preferably the clamp 6 consistsv `and at its other end is reame? a clamp 24 adapted to grip the tube 14 and e5 whose position on the arm 23 vmay be adjusted y a screw 72 or other means. This clamp 24 as illustrated by Figs. 1, 2 and 6 preferably consists 'of two jaws or blocks 25 secured together by a wedge 26 and arranged between the limbs 27 of a bracket 28 so that they can neither turn in nor be pushed out of the bracket 28. This bracket 28 is mounted on a rod or pin 29, preferably having ser-4 rations or the like 30 so that it cannot rotate about its own axis. This rod or pin 29 is carried bythe arm 23. Within the tube 14 a rod 31 is arranged which is secured at its the roller 19. The end of the tube which is "manner, for example, through the pipe or passage 34 in the ram 3 and moves the cylinder 4 endways on the sole plate 1. The cylinder 4 carries the clamp 6- and tube 14 i with it. Since the clamp 24 can only move in a circle aboutl the center of the spindle 12 lthe end of the-tube 14-is carried round and the tube is bent into shape.

' The mandrel 33 A(Fig. 7) is for the pur- A pose of` assistingin the control of the bending` operation and of'preventing .the tube 14 being` distorted at the beginning of the bend and is preferably located a suitable distance in front ofthe center line of the roller 19 'and axis 12. This center line is marked 35- on Figs. 7 to 12.v The center of themandrel 33 maybe on the line 35 or it may be at any suitable distance from the line 35. for example, the positionshown by Fig.' 7 is about the preferred distance. Before the bending operation commences the rod 31 is centrally within the tube 14 and as the bending 'proceeds the mandrel falls from the center due to the curvature .of the bend) andas shown by Fig. 7.

Fig. 8 illustrates a'form of mandrel similar to Fig. 7 Abut between the head 33 and a collar 36 a plurality of loose washers 37 are mounted on a square or like shaped portion of the rod 31. These washers 37 are provided with slots 38 so as to permit the movement -of the rod 31. The washers near the head 33 have a diameter somewhat smaller thaxi the diameter of the head 33 and those nected to the head 39, which is of cylindrical shape, by a ball and socket joint 41. Further f lor the like as shown by dotted lines. In this.

heads may be iitted by ball and socket joints case and in the arrangement illustrated bv Fig. 10 the rod 31 remains centrally within the tube 14 while the head 40 swivels.

. Fig. 12 illustrates a form of mandrel in which the head 40 is connected to the head 39 by a ball and socket joint 4l and both heads 39 and 40 are expandible. In this case the rod 31 is in the form ofa sleeve fitted to the head 39. The head 40 is split into two or moving but if desired it may be provided with gearing so that its motion synchronizes with the travel of the cylinder 4 and tube 14. The clamp 24 when the spindle 12 is free moving, cannot rotate about its own axis but when the spindle 12 is geared it may swivel about its vertical center line. In order that the tube may not be distorted at the clamp 24 a block 45isA preferably located adjacent to the clamp blocks or jaws 25.

lbe arranged on the inner side of the bend and would have a small clearance space `46 so as to support the tube 14; the bend commencing atthe edge 47 ofthe clamp jaws 25. .The innersurface of thisblock 45' would be rounded.

Fig. 14 illustrates la similar arrangement to that shown by Fig. 13 but 'the block 45 in this case is formed in one with the blocks 25 and extends right around the tube 14.

Fig. 15 illustrates anotherform in which the blocks 45 are seperate from the blocks 25 but there is no clearance space 46 and the blocks 45 embrace the tube 14. F ig. 16 illustrates the block 45 formed in one with the blocks 25 and while there is no clearance space 46 there is a clearance space between comparatively largel diameter are to be bent. a mandrel may be lnserted into the end of the tube 14 in the clamp 24. As illustrated by Fig. 17 this mandrel may be of the expanding type and may consists of a plug 51 having a divided head 52 and slotted arms 53 which may be expanded bv the conical head 54 and screwed rod 55. Fig. 18 illus- 'trates a form of mandrel in the clamp 24 which does not expandand which consists of a plug 56 having a rod 57 and head 58. The rod 57 may be replaced bv a chain or entirely omitted.

When it is .desired to bend a'tube which .has .already been bent, that is, to put a double bend on the tube the forms of clamp illustrated by Figs. 19, 20 and 21 or Figs.

22, 23 and 24 may be used.

,In these two modified forms of clamp the blocks or jaws 25 are provided with teeth or serrations 59 which engage similar teeth on the limbs 27 of the bracket 28. The bent tube is placed between the blocks 25 which are adjusted to suit the bend and then these blocks are secured together by the wedge 26.

Figs. 25, 26 and 27 are diagrammatic- `views illustrating the operation of the machine. In Figs. 26 and 27 .the position of the bent tube is shown by dotted lines. These views will be readily understood by the foregoing description of the operation of the machine. Fig. 28 is a diagram of a slightly modied form of machine.

In this case a fixed guide plate 60 takes the place of the surface of the Vcylinder against which the tube 14 is clamped and the tube is clamped to the cylinder as before or if desired the cylinder may be dispensed with and the tube 14 forced endways by any other suitable means.

In Fig. 29 a roller 61 takes the place of the-fixed guide 60.

, tance and as the c linder 4 mo s for ards This block, as illustrated bv Fig. 13. wouldv 'V Ve w this roller is carried around either by the cylinder, the friction of the tube, or similar means.

In Fig. 31 the face of the cylinder is replaced by roller 61 and the roller 62 moves around as before. The roller 62 will strengthen or reinforce the arm 23 during the beginning of the bend.

Instead of the face of the cylinder 4 being used to support the tube during the bending and help to control the bending action a pluralityof pressure rollers may be substituted and lche tube 14 would pass same by suitable means.

This machine may be used for bendin tubes into spirals or volutes.l As illustrate by Figs. 32 and 33 the spindle or axis 12 maybe mounted horizontally ninstead 0f "ertically and would be carried by a carriage 63 adapted to run on rails or guides 64. As the tube is bent into a circle the carriage would be travelled by suitable means so thatI the the coiled tube.

The sole plate 1 would be pivoted suitably at the bending end instead of at the other end 2 so that the tube "14 as it was l moved forward would bein alignment with of the coils. The spindle 12 is 4preferablyl provided with a counter-balance lweight or the like.

The rollersreferred to can also be provided with gearing enabling them to be moved out as the tube is fed past the guide rollers and thus form a volute. In bendin coils or volutes stops- 7 3 operated automatically would be arranged so that as the tube was fed forwards intermittently by the clams woul be gri lped and prevented -from beingadrawn bac by the clamp 6.

' y dispensing with Athe mandrels rods may be bent as desired.

By reversing the operation of the machine tubes already bent may be straightened.

I claim.q 1 1.A tube bending machine comprising a supporting element; a cylinder and a ram so mounted thereon` as to provide relative movement ltherebetween; means I' for clamping a tube 'to be bent to said cylinder; a guide roller for said tube; an axis; an arm mounted on said axis; and a clamp-member carried by said arm adapted to en age said tube, whereby thevlatter may be ent upon a movement of the same.

2. A tube bending machine comprising a pivoted sole plate; a cylinder and ram so mounted thereon as to provide relative movement therebetween; said cylinder having a face portion extending longitudinally thereof; means for clamping a tube to bebent on said face; a guide roller disposed on the side of said tube opposite to the said cylinder; and means for holding said pivoted sole elate rigid after its position has been adjust 3. A structure comprising a plate; a cylinder -and ram carried thereby; means for clamping a tube to be bent to said cylinder; a ide roller; an axis; an arm mounted on said axis; a rod carried by said arm; a clamp bracket so mounted on said rod as to permit said bracket to move in a preproper pitch is given to v 6 advancing and retreating the tube said clamp bracket; and means for securing said jaws together so as to clamp said tube.

4. A machine compris ing endways a tube to be nt; an axis located atJ a distance from the longitudinal center line'of said tube equal to the radius of the bend desired; an arm mounted on said axis; a tube clamp carried by said arm; guide roller; a mandrel head located approximatel on a line assing through said axis an at lit ang es to said tube; and a second man l head located in advance of said first-mentioned mandrel head, one of said mandrel lheads having an integral neck portion secured to the other.

5. A machine comprising means adapted to move endways a tube to be bent; an axis located at a distance from the longitudinal center line of said tube equal to the radius of the bend desired; an arm mounted on said axis; a tube clamp carried by said arm; a tube ide roller; and an xpandible mandrel ead located approximately on a line passing through said axis and at right an- ^g'les to said tube, said head comprising a means for movplurality of movable parts and a wedging member therefor.

6. A machine comprising a plate; means mounted thereon and adapted to carry a tube. to be bent and to move the same endways; an axis located at a distance from tli'e longitudinal center line of said tube equal to the radius of the bend desired; an arm mounted on said axis; a tube clamp carried b said arm; a tube guide roller; an expandib e mandrel head located approximately on a line passing through said axis and at right an les to said tube; a second expandible man rel head located in advance of said first-mentioned mandrel head, and an intregral neck portion extending from one mandrel to the other.

7. A machine comprising a plate; means mounted thereon and adapted to vcarry a tube to be bent and to move the same endways; an axis located at a distance from the longitudinal center line of said tube equal to the radius of the bend desired; an arm mounted on said axis; a tube clamp carried bv said arm; a tube guide roller; an expandible mandrel head located approxilmately on a line passing through said axis and at right an les to said tube; a second expandible man rel head located in advance vof said first-mentioned mandrel head; a ball-and-socket joint between said mandrel heads; members havin wedge surfaces located within said man rel heads; and means-for so operating said members as to expand said heads.

8. A machine comprising a plate; means mounted thereon and adapted to carry a tube to be bent and to move the same endways; an adjustable guide roller; an axis;

an arm mounted on said axis; a clamp bracket carried by said arm; a pair of jaws itted to said bracket and adapted to grip said tube; members extending longitudinally from said jaws and around said tube; and bell-mouth or curved end parts at the extremities of said extending members.

9. A vmachine comprising a plate; means mounted thereon and adapted to carry a tube to be bent and to move the same endways; a guide roller; an axis; an arm mounted` on said axis; a clamp bracket carried by said arm; a pair of jaws fitted to said bracket and adapted to grip said tube; members extending from said jaws longitudinally around said tube; and bell-mouth or curved `end parts at the extremities of said extending members'forming a clearance space between the gripping parts of said aws or blocks and the said extending memers. l0. A machine comprising a plate; means mounted thereon and adapted to carry a tube to be bent and to move the same endways; an adjustable guide roller; an axis; an arm mounted on said axis; a -tube clamping' member carried by said arm; and a mandrel located within the part of said tube within said tube clamping member.

`11. A machine comprising a plate; means mounted thereon and adapted to carry a tube to be bent and to move the same endways; a guide roller; an axis; an arm mounted on said axis; a tube clamping member carried by said arm; an expanding mandrel located within the part of said tube within said tube clamping member; and

means whereby said expanding mandrel may be expanded.

12. A structure comprising a sole plate; means mounted thereon and adapted to carry a tube to be bent and to move the same endways;. an adjustable guide roller; an axis; an arm mounted on said axis; a clamp bracket carried by said arm; jaws adapted to grip said tube and fitted to said 'clamp bracket; teeth or serrations on said jaws; and wedging means for securing said jaws to said clamp bracket. t

13. A machine comprising a plate; means mounted thereon and adapted to carry a tube to be bent and to move the same endways; an adjustable guide roller; a carriaUe adapted to ltravel in a direction at right angles to the endways moving tube; a spindle carried by said carriage; an arm mounted on said spindle; a tube clamp carried by said arm; a frame; an adjustable carriave mounted on said frame; and rollers carried by said frame for guiding said tube as it is being bent.

14. A tube bending machine comprising a plate; means mounted thereon and adapted to carry a tube to be bent and to move the same endways; an adjustable guide roller; an axis; an arm mounted on said axis; a tube clamping member carried by said arm; and a guide roller adapted to move with the bent portion of the tube as the `bend is being formed.

CARL ROBERT HUGO BONN. 

